Incozol BH Aldimine Latent Curing Agent

Transcription

1 Incozol BH Aldimine Latent Curing Agent Incozol high performance additive for use in: flexible joint sealants elastic bonding adhesives general sealing & bonding compounds

2 Joint Sealing Solutions Introduction Joints and openings between construction elements can be found in different parts of a construction, e.g. between precast concrete elements in facades, around windows and doors, at the connection between floors and walls, in storage tanks, etc. Joint sealants have to meet various requirements depending on the function and location of the respective joint. The purpose of joint sealing is generally to: Prevent passage of media (air, water, chemicals, smoke, etc.) Provide thermal and sound insulation Enhance the visual appearance of the whole construction Why elastic sealing? Building and civil engineering structures consist of individual elements which exhibit relative movements to each other. There are two kinds of such movements: Expansion of building elements Thermal movements Changes in temperature result in an expansion or contraction of the building elements, i.e. joints become larger (extension) or smaller (compression) continuously. Thermal movements are considerable in the case of big elements or when different materials are used (e.g. brick wall and vinyl window frame). Structural movements These movements are caused by settlements of the structure, vibrations or other loads (wind etc.) and consequently deform the joint dimensions and hence may stress the sealing material significantly. Structural movements often result in shear stress acting on the sealant. Advantages of elastic joint sealants In comparison to rigid materials (e.g. cement or mortar), high performance elastic joint sealants are able to accommodate thermal and structural movements without breaking or losing the adhesion to the building elements. These sealants thus retain their original functionality throughout their whole life cycle and provide long-term tightness. Contraction of building elements Shear loads 2

3 Incozol BH Incozol BH is an aldimine latent curing agent that hydrolyses on exposure to moisture, yielding a reactive amine crosslinker and benzaldehyde. It has been specially designed for one component PU systems and is suitable for use with both aromatic and aliphatic prepolymers. H H R H C N R aldimine + H 2O water [cat. H+] R-NH 2 amine + H C O R aldehyde N R N isocyanate R NCO O R C N N H H urea R Why use a latent curing agent? Latent curing agents are particularly beneficial in high-build polyurethane systems because they promote faster through-cure with no CO2 gas evolution. In addition, they will accelerate the cure of low NCO containing prepolymers. Incozol BH also exhibits good in-can stability with aromatic prepolymers which makes it more suited to 1K aromatic systems than standard latent curing agents. Typical Applications: Flexible joint sealants, elastic bonding adhesives, general sealing & bonding compounds Features Benefits Prevents the generation of CO2 which can lead to gassing Bubble free & defect free films Enables bubble free curing at elevated temperature & humidity levels Suitable for use in different climatic conditions Suitable for use in aromatic & aliphatic prepolymers Greater formulation flexibility Very low viscosity Ideal for high solids systems Very good storage stability with aromatic isocyanates Improved handling over standard latent hardeners Low temperature crystallisation stability (down to -20ºC) Ease of handling & storage. Reduced energy costs (no heating required) Excellent shelf-life Enhanced storage capabilities 3

4 Incozol BH in Elastic PU Joint Sealants Guide formulation for 1K elastic sealant 1. Prepolymer 2. Latent Hardener 3. Catalyst 4. Plasticiser 5. Filler 6. Pigment 7. Filler Total Material Desmoseal M280 Incozol BH Oleic Acid Diisodecyl phthalate Dried CaCO3 TiO2 PVC Parts by Weight Properties Skinning time (min) Shore A hardness Tensile strength (MPa) Elongation at break (%) E-modulus 100% (MPa) Tear propagation resistance (N/mm) Standard ISO 868 ISO 37 ISO 37 ISO 8339 ISO 34 Manufacturing Instructions Disperse formulation for 20 minutes at 70ºC Formulation Guidelines For each wt% NCO in the formulation, approx. 3-4% Incozol BH should be employed. Example: A formulation with an NCO content of 0.65% needs approx % Incozol BH. The curing speed, particularly the catalysis, depends on the individual formulation. This is because the reactivity of the latent hardener is dependent on the acidity/ph value of the system. Typical catalysts for the latent hardener are organic acids such as Oleic Acid, Benzoic Acid, Salicylic Acid, Maleic Acid, Fumaric Acid, Succinic Acid, Adipic Acid, Toluenesulfinic Acid and similar types. Typical amounts are 0.02% to 1% acid but this may vary strongly from system to system. The reactivity will increase with the amount and the acidity level of the acid used. The catalyst used for the catalysis of the NCO-water reaction may be decreased to a minimum or even to zero. 4

5 Sealing Solutions Sealing Solutions for Movement Joints The main requirements for a sealant in this application are: Low modulus even at low temperatures Excellent weatherability High colour stability and UV resistance Good adhesion to porous and non-porous substrates High tear resistance Paintability Resistance to cleaning procedures Defect-free curing Typical application example Sealing of joints between precast concrete elements Sealing Solutions for Connection Joints The main requirements for a sealant in this application are: Broad adhesion range to porous and non-porous substrates Compatibility to various substrates including plastics, paints and coatings High colour stability and UV resistance Excellent weatherability Paintability Typical application examples Sealing of joints between window frames and bricks of concrete slabs Sealing Solutions for Floor Joints Sealants used for floor joints are required to have: High mechanical strength High abrasion resistance Good chemical resistance Excellent adhesion properties Depending on the area of application, additional properties may be required. Typical application examples Sealing of floor connection joints in factories Sealing of joints in car parks and pedestrian areas 5

6 Incozol BH in Elastic Bonding Adhesives Guide formulation for 1K spreadable/trowel applied adhesive 1. Prepolymer 2. Latent Hardener 3. Catalyst 4. Plasticiser 5. Filler 6. Pigment 7. Thixotropic Agent 8. Filler Total Material Desmoseal M280 Incozol BH Oleic Acid Diisodecyl phthalate Dried CaCO3 TiO2 Fumed Silica PVC Parts by Weight For a non-sag adhesive with initial tack refer to above formulation also Properties Standard Skinning time (min) Shore A hardness Tensile strength (MPa) Elongation at break (%) Tensile shear - oak (MPa) Tear propagation resistance (N/mm) ISO 868 ISO 37 ISO 37 ISO 4587 ISO 34 Manufacturing Instructions Disperse formulation for 20 minutes at 70ºC Formulation Guidelines For each wt% NCO in the formulation, approx. 3-4% Incozol BH should be employed. Example: A formulation with an NCO content of 0.65% needs approx % Incozol BH. The curing speed, particularly the catalysis, depends on the individual formulation. This is because the reactivity of the latent hardener is dependent on the acidity/ph value of the system. Typical catalysts for the latent hardener are organic acids such as Oleic Acid, Benzoic Acid, Salicylic Acid, Maleic Acid, Fumaric Acid, Succinic Acid, Adipic Acid, Toluenesulfinic Acid and similar types. Typical amounts are 0.02% to 1% acid but this may vary strongly from system to system. The reactivity will increase with the amount and the acidity level of the acid used. The catalyst used for the catalysis of the NCO-water reaction may be decreased to a minimum or even to zero. 6

7 Sealing & Bonding Solutions Waterproofing and bonding with only one product 1K PU elastic adhesives formulated to include Incozol BH provide a waterproof layer and excellent resistance to thermal movement deformation. These properties make them ideal for external bonding applications such as balconies, roofs and other areas exposed to water. Sealing, bonding & filling all in one Compounds can be formulated which remain permanently elastic and resistant to vibration and movement from temperature changes. They can also provide incredibly strong, permanent adhesion with excellent tack and non-sag properties. In addition, they can be used as waterproof, permanently flexible fillers for wide gaps. A versatile solution Incozol BH provides moisture triggered technology which accelerates cure times. It also enables water and weatherproof compounds to be developed which can be used inside and outside. They are easy and ready-to-use and are a versatile alternative to mechanical fixing. 7

8 Manufacturers of specialist resins & polymers: Oxazolidines Waterborne epoxy curing agents Waterborne polyurethane dispersions Incorez Limited Miller Street Preston Lancashire PR1 1EA England t: +44 (0) f: +44 (0) e: w: ISSUE 1-03/13